Objective To describe the clinical characteristics of idiopathic ventricular fibrillation (IVF) with fragmented QRS complex (f-QRS) and J wave in resting electrocardiogram. Methods We reviewed data from 21 case su...Objective To describe the clinical characteristics of idiopathic ventricular fibrillation (IVF) with fragmented QRS complex (f-QRS) and J wave in resting electrocardiogram. Methods We reviewed data from 21 case subjects in our hospital who were resuscitated after cardiac arrest due to IVF and assessed the prevalence of f-QRS and J wave in resting electrocardiogram (ECG). All the case subjects were classified among three groups based on the electrocardiographic morphology: group I, both f-QRS and J wave were observed (n = 6), group II, only J wave was observed (n = 9), group III, neither f-QRS nor J wave was observed (n = 6). Population characteristics, history of syncope or sudden cardiac arrest, incidence of ventricular fibrillation (VF), and circumstance of VF were evaluated among the three groups. Results The incidence of index events (syncope, survived cardiac arrest and VF episodes recorded in implantable cardioverter defibrillator (ICD) or pacemakers) was 13.4 ~ 5.6 per-year in group I, 10.8 ~ 3.9 per-year in group II, and 9.8 -4- 4.2 per-year in group HI. There were significant differences in incidences among the three groups, the most frequent index events were observed in group I. The hazard ratio for incidence was 3.2 (95%CI, 1.1-7.9; P = 0.01). The history and circumstance of the index events were different among the groups. In group I, all the index events occurred during sleep in early morning. In group II, four subjects suffered VF during strenuous physical activities or agitation state, two during sleep in early morning, three in usual activity. In group III, one subject suffered VF during sleep in early morning, one in agitation state, four in usual activity. Conclusions This study suggests that the IVF patients with the combined appearance of f-QRS and J wave in the resting ECG suffer an increased risk of VF, this subgroup of IVF patients has a unique clinical feature.展开更多
Background Many epidemiological studies analyze the relationship between hyperuricemia and cardiovascular outcomes. This observational prospective study investigates the association of serum uric acid (SUA) levels w...Background Many epidemiological studies analyze the relationship between hyperuricemia and cardiovascular outcomes. This observational prospective study investigates the association of serum uric acid (SUA) levels with adverse cardiovascular events and deaths in an elderly population affected by advanced atherosclerosis. Methods Two hundred and seventy six elderly patients affected by advanced atherosclerosis (217 males and 59 females; aged 71.2 ±7.8 years) were included. All patients were assessed for history of cardiovascular disease, cancer, obesity and traditional risk factors. Patients were followed for approximately 31 ±11 months. Major events were recorded during follow-up, defined as myocardial infarction, cerebral isehemia, myocardial and/or peripheral revascularization and death. Results Mean SUA level was 5.47 ±1.43 mg/dL; then we further divided the population in two groups, according to the median value (5.36 mg/dL). During a median follow up of 31 months (5 to 49 months), 66 cardiovascular events, 9 fatal cardiovascular events and 14 cancer-related deaths have occurred. The patients with increased SUA level presented a higher significant incidence of total cardiovascular events (HR: 1.867, P = 0.014, 95% CI: 1.134-3.074), The same patients showed a significant increased risk of cancer-related death (HR: 4.335, P = 0.025, 95% CI: 1.204-15.606). Conclusions Increased SUA levels are independently and significantly associated with risk of cardiovascular events and cancer related death in a population of mainly elderly patients affected by peripheral vasculopathy.展开更多
This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-re...This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-resolution grain-size variation, sensitive population, geochemical indexes and magnetic susceptibility. The core covers a time span of 120 years by 21~pb dating and was sampled at 1-2 cm intervals. Grain size, geochemical elements, and physical parameters were analyzed. The results indicate that the sediment of the core is mainly composed of silt and clay, as well as groups of interbedded silt, clay silt, and clay. Vertically, the grain size pattern was controlled by seasonal variations in water discharge and by the sediment input in winter from the abandoned Huanghe River delta. River flooding caused extreme values in all our measured parameters. We identified more than 20 flood events that occurred since 1887 using the physical parameter analysis method. The environmentally sensitive component of sediment grain size (14.32-96.39 gm) contribution〉30%, Zr/Rb ratio〉l.5, and magnetic susceptibility〉16 were selected as the criteria for flood identification generally. We also found that floods that had taken place in the upstream, midstream, or downstream parts of the river were clearly identified by these indexes while the large-scale floods that covered the whole drainage area did not leave clear indications in the sediment record. This study for identification of flood events is of great significance for understanding hyperpycnal current sedimentation as well as for forecasting of floods.展开更多
Between 1876 and 1878 a large-scale drought occurred in China. This is a major meteorological disaster and an extreme climate event despite the cold climate at the end of the Little Ice Age. In this paper the dynamic ...Between 1876 and 1878 a large-scale drought occurred in China. This is a major meteorological disaster and an extreme climate event despite the cold climate at the end of the Little Ice Age. In this paper the dynamic evolution of the occurrence and development of the drought is reproduced on the basis of historical literature records. These were used to calculate the yearly numbers of drought-hit counties and to determine the spatial distribution in addition with concomitant famine, locust plague and pestilence epidemic for each of the three years. The persistent drought disaster spread over 13 provinces with its center in Shaanxi, Henan and Shanxi provinces, where the continuous non-soaking rain period exceeded 340 days. Conclusively, it is more severe than the worst drought (1928-1930) in the 20th century. This drought disaster of 1876-1878 took place in the descending phase of the 11th sunspot activity period and the start of the 12th period. It also happened during a spell of frequent E1 Nino events and corresponds with an extremely strong E1 Nino.展开更多
Background Atherosclerotic plaques indicate the occurrence of ischemia events and it is a difficult task for clinical physicians. Grape seed proanthocyanidin extract (GSPE) has been reported to exert an antiatheroge...Background Atherosclerotic plaques indicate the occurrence of ischemia events and it is a difficult task for clinical physicians. Grape seed proanthocyanidin extract (GSPE) has been reported to exert an antiatherogenic effect by inducing regression of atherosclerotic plaques in animal experimental studies. In this study, the antiatherogenic effect of GSPE has been investigated in clinical use. Methods Consecu- tive 287 patients diagnosed with asymptomatic carotid plaques or abnormal plaque free carotid intima-media thickness (CIMT) were ran- domly assigned to the GSPE group (n = 146) or control group (n = 141). The patients in the GSPE group received GSPE 200 mg per day orally, while patients in the control group were only enrolled in a lifestyle intervention program. Carotid ultrasound examination was per- formed at baseline and 6, 12, 24 months during follow-up. Mean maximum CIMT (MMCIMT), plaque score, echogenicity of plaques and ischemic vascular events were recorded. Results As anticipated, after treatment, GSPE resulted in significant reduction in MMCIMT pro- gression (4.2% decrease after six months, 4.9% decrease after 12 months and 5.8% decrease after 24 months) and plaque score (10.9% de- crease after six months, 24.1% decrease after 12 months and 33.1% decrease after 24 months) for the primary outcome, while MMCIMT and plaque score were stable and even increased with the time going on in control group. The number of plaques and unstable plaques also de- creased after treatment of GSPE. Furthermore, the carotid plaque can disappear after treatment with GSPE. The incidence rate for transitory ischemic attack (TIA), arterial revascularization procedure, and hospital readmission for unstable angina in GSPE group were statistically significant lower (P = 0.02, 0.08, 0.002, respectively) compared with the control group. Conclusions GSPE inhibited the progression of MMCIMT and reduced carotid plaque size in GSPE treated patients, and with extended treatment, the superior efficacy on MMCIMT and carotid plaque occurred. Furthermore, the GSPE group showed lower rates of clinical vascular events.展开更多
An alternative method was introduced for voltage sag source location based on S and TT transformed disturbance powers. It is done to avoid the wrong and inconclusive detection of conventional disturbance power method ...An alternative method was introduced for voltage sag source location based on S and TT transformed disturbance powers. It is done to avoid the wrong and inconclusive detection of conventional disturbance power method proposed in the literature. Unlike in the case of the traditional method, the proposed method first transforms the recorded voltage and current during the sag event to some special features before calculating the new version of disturbance powers. The effectiveness of the proposed method has been verified through simulation and actual data from an industrial power system. The results show that the presented method can correctly detect the location of voltage sag source.展开更多
Following disastrous flooding in several river valleys over eastern China in 1755, serious flooding occurred in the middle and lower reaches of the Yellow River in 1756 and 1757, a rarely seen precipitation pattern of...Following disastrous flooding in several river valleys over eastern China in 1755, serious flooding occurred in the middle and lower reaches of the Yellow River in 1756 and 1757, a rarely seen precipitation pattern of north-flood and south-drought in China for two successive years. This is a serious meteorological disaster and extreme climatic event taking place under the climatic background of a warm phase of the Little Ice Age. In this paper, by means of historical literature records, the rainy and flooding situation and the weather characteristics of these years are reconstructed and the maps depicting areas of prolonged rain, flood and concomitant famine, insect pest, and pestilence are made. The results show that, in 1755, the middle and lower reaches of the Yellow River and the Yangtze River, and the Huaihe River Basin experienced a prolonged rainy season with multiple torrential rain events. The continuous rainy period exceeded 40 days in the Huang-Huai Region. An early Meiyu occurred, and the duration of the Meiyu period in the lower Yangtze River Basin was 43 days, the longest in the 18th century. Particularly in Nanjing the annual rainfall of 1755 was 1,378 mm, the highest record of the 18th century. The year of 1755 is characterized by lower temperature in summer, early frost in autumn, and heavy snowfall and freezing rain in winter. These characteristics are extremely similar to those of 1823 and 1954, two typical years of extreme rainfall. And all these three years with extreme precipitation axe corresponding to the minimum phase of the solar activity cycle.展开更多
The study provides one of the first lines of evidence showing linkages between Antarctic phytoplankton abundance and composition in response to ENSO, based on historical reconstruction of sediment biomarkers. In addit...The study provides one of the first lines of evidence showing linkages between Antarctic phytoplankton abundance and composition in response to ENSO, based on historical reconstruction of sediment biomarkers. In addition to sediment biomarkers, field measured and remote sensing data of phytoplankton abundance were also recorded from Prydz Bay, Eastern Antarctica. Com-munity structure of field measured phytoplankton showed significant El Ni?o/La Ni?a-related succession during 1990 to 2002. In general, the number of algae species decreased during El Ni?o and La Ni?a years compared to normal years. Austral summer monthly variation of remotely sensed chlorophyll-a (Chl-a), particulate organic carbon (POC), and sea surface temperature (SST) indicated that ENSO impacted the timing of phytoplankton blooms during 2007 to 2011. Phytoplankton blooms (indicated by Chl-a and POC) preceded the increases in SST during El Ni?o years, and lagged behind the SST increases during La Ni?a years. Stratigraphic record of marine sedimentary lipid (brassicasterol, dinosterol and alkenones) biomarkers inferred that the proportions of different algae (diatoms, dinoflagellates and haptophytes) changed significantly between El Ni?o and La Ni?a events. The relative proportion of diatoms increased, with that of dinoflagellates being decreased during El Ni?o years, while it was reversed during La Ni?a years.展开更多
文摘Objective To describe the clinical characteristics of idiopathic ventricular fibrillation (IVF) with fragmented QRS complex (f-QRS) and J wave in resting electrocardiogram. Methods We reviewed data from 21 case subjects in our hospital who were resuscitated after cardiac arrest due to IVF and assessed the prevalence of f-QRS and J wave in resting electrocardiogram (ECG). All the case subjects were classified among three groups based on the electrocardiographic morphology: group I, both f-QRS and J wave were observed (n = 6), group II, only J wave was observed (n = 9), group III, neither f-QRS nor J wave was observed (n = 6). Population characteristics, history of syncope or sudden cardiac arrest, incidence of ventricular fibrillation (VF), and circumstance of VF were evaluated among the three groups. Results The incidence of index events (syncope, survived cardiac arrest and VF episodes recorded in implantable cardioverter defibrillator (ICD) or pacemakers) was 13.4 ~ 5.6 per-year in group I, 10.8 ~ 3.9 per-year in group II, and 9.8 -4- 4.2 per-year in group HI. There were significant differences in incidences among the three groups, the most frequent index events were observed in group I. The hazard ratio for incidence was 3.2 (95%CI, 1.1-7.9; P = 0.01). The history and circumstance of the index events were different among the groups. In group I, all the index events occurred during sleep in early morning. In group II, four subjects suffered VF during strenuous physical activities or agitation state, two during sleep in early morning, three in usual activity. In group III, one subject suffered VF during sleep in early morning, one in agitation state, four in usual activity. Conclusions This study suggests that the IVF patients with the combined appearance of f-QRS and J wave in the resting ECG suffer an increased risk of VF, this subgroup of IVF patients has a unique clinical feature.
文摘Background Many epidemiological studies analyze the relationship between hyperuricemia and cardiovascular outcomes. This observational prospective study investigates the association of serum uric acid (SUA) levels with adverse cardiovascular events and deaths in an elderly population affected by advanced atherosclerosis. Methods Two hundred and seventy six elderly patients affected by advanced atherosclerosis (217 males and 59 females; aged 71.2 ±7.8 years) were included. All patients were assessed for history of cardiovascular disease, cancer, obesity and traditional risk factors. Patients were followed for approximately 31 ±11 months. Major events were recorded during follow-up, defined as myocardial infarction, cerebral isehemia, myocardial and/or peripheral revascularization and death. Results Mean SUA level was 5.47 ±1.43 mg/dL; then we further divided the population in two groups, according to the median value (5.36 mg/dL). During a median follow up of 31 months (5 to 49 months), 66 cardiovascular events, 9 fatal cardiovascular events and 14 cancer-related deaths have occurred. The patients with increased SUA level presented a higher significant incidence of total cardiovascular events (HR: 1.867, P = 0.014, 95% CI: 1.134-3.074), The same patients showed a significant increased risk of cancer-related death (HR: 4.335, P = 0.025, 95% CI: 1.204-15.606). Conclusions Increased SUA levels are independently and significantly associated with risk of cardiovascular events and cancer related death in a population of mainly elderly patients affected by peripheral vasculopathy.
基金Supported by the National Natural Science Foundation of China(Nos.41206073,41376079,41206051,41206052)the China Geological Survey(Nos.1212010611401,200900501)
文摘This paper presents a paleoflood study to determine the flood frequency of the Changjiang River, based on core cj0702, taken from the Changjiang River subaqueous delta. We identified flood deposits by means of high-resolution grain-size variation, sensitive population, geochemical indexes and magnetic susceptibility. The core covers a time span of 120 years by 21~pb dating and was sampled at 1-2 cm intervals. Grain size, geochemical elements, and physical parameters were analyzed. The results indicate that the sediment of the core is mainly composed of silt and clay, as well as groups of interbedded silt, clay silt, and clay. Vertically, the grain size pattern was controlled by seasonal variations in water discharge and by the sediment input in winter from the abandoned Huanghe River delta. River flooding caused extreme values in all our measured parameters. We identified more than 20 flood events that occurred since 1887 using the physical parameter analysis method. The environmentally sensitive component of sediment grain size (14.32-96.39 gm) contribution〉30%, Zr/Rb ratio〉l.5, and magnetic susceptibility〉16 were selected as the criteria for flood identification generally. We also found that floods that had taken place in the upstream, midstream, or downstream parts of the river were clearly identified by these indexes while the large-scale floods that covered the whole drainage area did not leave clear indications in the sediment record. This study for identification of flood events is of great significance for understanding hyperpycnal current sedimentation as well as for forecasting of floods.
基金supported by the National Science and Technology Support Program of China under Grant No.2007BAC29B-01,and Grant No. 2010CB950103 under China Global Change Research Program
文摘Between 1876 and 1878 a large-scale drought occurred in China. This is a major meteorological disaster and an extreme climate event despite the cold climate at the end of the Little Ice Age. In this paper the dynamic evolution of the occurrence and development of the drought is reproduced on the basis of historical literature records. These were used to calculate the yearly numbers of drought-hit counties and to determine the spatial distribution in addition with concomitant famine, locust plague and pestilence epidemic for each of the three years. The persistent drought disaster spread over 13 provinces with its center in Shaanxi, Henan and Shanxi provinces, where the continuous non-soaking rain period exceeded 340 days. Conclusively, it is more severe than the worst drought (1928-1930) in the 20th century. This drought disaster of 1876-1878 took place in the descending phase of the 11th sunspot activity period and the start of the 12th period. It also happened during a spell of frequent E1 Nino events and corresponds with an extremely strong E1 Nino.
文摘Background Atherosclerotic plaques indicate the occurrence of ischemia events and it is a difficult task for clinical physicians. Grape seed proanthocyanidin extract (GSPE) has been reported to exert an antiatherogenic effect by inducing regression of atherosclerotic plaques in animal experimental studies. In this study, the antiatherogenic effect of GSPE has been investigated in clinical use. Methods Consecu- tive 287 patients diagnosed with asymptomatic carotid plaques or abnormal plaque free carotid intima-media thickness (CIMT) were ran- domly assigned to the GSPE group (n = 146) or control group (n = 141). The patients in the GSPE group received GSPE 200 mg per day orally, while patients in the control group were only enrolled in a lifestyle intervention program. Carotid ultrasound examination was per- formed at baseline and 6, 12, 24 months during follow-up. Mean maximum CIMT (MMCIMT), plaque score, echogenicity of plaques and ischemic vascular events were recorded. Results As anticipated, after treatment, GSPE resulted in significant reduction in MMCIMT pro- gression (4.2% decrease after six months, 4.9% decrease after 12 months and 5.8% decrease after 24 months) and plaque score (10.9% de- crease after six months, 24.1% decrease after 12 months and 33.1% decrease after 24 months) for the primary outcome, while MMCIMT and plaque score were stable and even increased with the time going on in control group. The number of plaques and unstable plaques also de- creased after treatment of GSPE. Furthermore, the carotid plaque can disappear after treatment with GSPE. The incidence rate for transitory ischemic attack (TIA), arterial revascularization procedure, and hospital readmission for unstable angina in GSPE group were statistically significant lower (P = 0.02, 0.08, 0.002, respectively) compared with the control group. Conclusions GSPE inhibited the progression of MMCIMT and reduced carotid plaque size in GSPE treated patients, and with extended treatment, the superior efficacy on MMCIMT and carotid plaque occurred. Furthermore, the GSPE group showed lower rates of clinical vascular events.
基金the financial support from the Universiti Kebangsaan Malaysia under the research grant UKM-DLP-2011-059
文摘An alternative method was introduced for voltage sag source location based on S and TT transformed disturbance powers. It is done to avoid the wrong and inconclusive detection of conventional disturbance power method proposed in the literature. Unlike in the case of the traditional method, the proposed method first transforms the recorded voltage and current during the sag event to some special features before calculating the new version of disturbance powers. The effectiveness of the proposed method has been verified through simulation and actual data from an industrial power system. The results show that the presented method can correctly detect the location of voltage sag source.
基金supported in part by the China Global Change Research Program(No.2010CB950103)the National Science and Technology Support Program of China(No.2007BAC29B01)
文摘Following disastrous flooding in several river valleys over eastern China in 1755, serious flooding occurred in the middle and lower reaches of the Yellow River in 1756 and 1757, a rarely seen precipitation pattern of north-flood and south-drought in China for two successive years. This is a serious meteorological disaster and extreme climatic event taking place under the climatic background of a warm phase of the Little Ice Age. In this paper, by means of historical literature records, the rainy and flooding situation and the weather characteristics of these years are reconstructed and the maps depicting areas of prolonged rain, flood and concomitant famine, insect pest, and pestilence are made. The results show that, in 1755, the middle and lower reaches of the Yellow River and the Yangtze River, and the Huaihe River Basin experienced a prolonged rainy season with multiple torrential rain events. The continuous rainy period exceeded 40 days in the Huang-Huai Region. An early Meiyu occurred, and the duration of the Meiyu period in the lower Yangtze River Basin was 43 days, the longest in the 18th century. Particularly in Nanjing the annual rainfall of 1755 was 1,378 mm, the highest record of the 18th century. The year of 1755 is characterized by lower temperature in summer, early frost in autumn, and heavy snowfall and freezing rain in winter. These characteristics are extremely similar to those of 1823 and 1954, two typical years of extreme rainfall. And all these three years with extreme precipitation axe corresponding to the minimum phase of the solar activity cycle.
基金financially supported by the National Natural Science Foundation of China (NSFC) (40876104, 41306202, 41376193, 41076134 and 41006118)the scientific research fund of Second Institute of Oceanography, SOA (JT1208 and JG1218)+1 种基金Chinese Arctic and Antarctic Administration Foundation (20110208)the special fund for polar environment comprehensive investigation and assessment (CHINARE 2014-04-04, 2014-01-04 and 2014-04-01)
文摘The study provides one of the first lines of evidence showing linkages between Antarctic phytoplankton abundance and composition in response to ENSO, based on historical reconstruction of sediment biomarkers. In addition to sediment biomarkers, field measured and remote sensing data of phytoplankton abundance were also recorded from Prydz Bay, Eastern Antarctica. Com-munity structure of field measured phytoplankton showed significant El Ni?o/La Ni?a-related succession during 1990 to 2002. In general, the number of algae species decreased during El Ni?o and La Ni?a years compared to normal years. Austral summer monthly variation of remotely sensed chlorophyll-a (Chl-a), particulate organic carbon (POC), and sea surface temperature (SST) indicated that ENSO impacted the timing of phytoplankton blooms during 2007 to 2011. Phytoplankton blooms (indicated by Chl-a and POC) preceded the increases in SST during El Ni?o years, and lagged behind the SST increases during La Ni?a years. Stratigraphic record of marine sedimentary lipid (brassicasterol, dinosterol and alkenones) biomarkers inferred that the proportions of different algae (diatoms, dinoflagellates and haptophytes) changed significantly between El Ni?o and La Ni?a events. The relative proportion of diatoms increased, with that of dinoflagellates being decreased during El Ni?o years, while it was reversed during La Ni?a years.